马占相思与厚荚相思树皮抽提物的比较研究

对马占相思树皮和厚荚相思树皮单宁进行定性和定量分析，模拟栲胶生产小试并对制取的栲胶进行质量分析。结果表明：两种树皮所含单宁均属缩合类单宁；绝干马占相思树皮含单宁高达36.75％，纯度为85．9％．单宁与非单宁之比为6．10，约2．34t气干树皮可生产1t栲胶，制得的栲胶不仅单宁含量高，颜色浅．而且鞣革渗透速度快,富有弹性．皮质好．证明马占相思树皮是一种优良的栲胶原料；绝干厚荚相思树皮含单宁仅9.56％．生产1t栲胶约需气干树皮4．96t，制得的栲胶含单宁53．32％．含非单宁46.47％．测得栲胶中多酚含量接近70％，可代替部分酚类物质用于制取高分子材料，可见大量的厚荚相思树皮也有生产栲胶的价值。

Comparative Study on Extracts from the Bark of Acacia mangium and Acacia crassicarpa

Tannin substances extracted from the bark of Acacia mangium and A, crassicarpa were qualitatively and quantitatively analyzed, and pilot production of vegetable tannin extract was simulated. The result shows that the tannin in both barks belongs to the condensed type. The absolutely dried A. mangium bark contains up to 36.75% of tannin, with 6. 10 of ratio of tannin to non-tannin. One ton of vegetable tannin extract can be obtained from about 2.34 tons of air dried bark. and the product has a high tannin content with a quality light colour, which can quickly permeate when tanning leather and make the leather good in elasticity and quality. So A. mangium bark is an excellent raw material for vegetable tannin extract. The absolutely dried A. crassicarpa bark contains only 9.56% of tannin, and it takes 4.96 tons of air dried bark to produce one ton of vegetable tannin extract. The product contains 53. 32% of tannin and 46. 47% of non-tannin. The content of polyphenol was up to 70%, which can be used as substitutes of phenols to make polymer materials; therefore, A. crassicarpa bark is also valuable in producing vegetable tannin extract.